Contactor.



PATENTED JULY 28, 1908.'

HILL.

CONTAGTOR.

APPLIGAITION FILED Emma, 1906.

INVENTEIR. GEEIRGE H. HiLL.

WITNESSES- UNITED STATES PATENT oEEroE;

GEORGE H. HILL, OF SGHENEGTADY, NEW YORK, ASSIGNOR TO' GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

conmc'ron.

Specification of I ettersPatent.

Patented July 28, 1908.

Application filed February 9, 1906. Serial No. 300,269.

To all "whom it may concern:

Be it known that I, GEORGE H. HILL, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Oontactors, of'which the following is a specification.

The present invention relates to the construction of power-operated switches or contactors, such as are employed in systems of motor control wherein the motor controller is composed of a number of separately-actuated switches or contactors the actuating electro magnets of which are controlled by a master controller. ary to construct the movable member of such switches of heavy castings connected togetherbysprings forthe urposeofpermitting the contact ti s to be rought into engagement with a siding motion and to be held together with spring pressure: This involves complicated and expensive construction.

In my prior application, Serial No. 187,287, filed Dec. 31, 1903, I'have disclosed a contactor whereih the objections to the old form of contactor arm are obviated bymaking the movable contactor member of a single strip of spring metal rigidly supportedat one end and so proportioned and arranged that roper en agement is made and maintained )etween t 1e contact tips. This form of arm has the further advantage over the old construction in that, by reason of its lightness, the electromagnet is permitted to lift it more quickly when energized. It has been found, however, that in order to obtain a ro er spring pressure between the contacts in t is construction, the spring arm should be under tension even when the lunger is in its lowest position,- thus largely e iminating the gain in rapidity of action an account of the lightness of the arm.=' It has further been found that the spring arm sometimes breaks adj acent its point of support after it has been operated a arge number of times.

The present invention'contemplates a construction wherein the, advantages without the disadvantages of my prior contactor are retained more perfect contact is secured, and the hfe of the'contacts prolonged.

To the above end the present invention consists in the construction and or anization of parts to be hereinafter describe and particularly pointed out in the claims.

It has long-been custom- In the accompanying drawing, Figure 1 shows partly in side elevation and partly in section a contactor arranged in accordance with the present invention, and Fig. 2 shows in cross-section a fragment of the contactor in the closed osition.

Reference eing had to the drawing, 1 represents an electromagnet suitably supported in a frame 2 and having a plunger 3. A contact 4 is su ported in'the usual way u on a slab of insu ation 2 at one side of the e ectromagnet. 5 isthe movable member or arm of the contactor and comprises a resilient strip of metal 6 provided at one end'thereof with an eye or sleeve 7 through which passes a bolt or shaft 8, thereby forming: a pivotal support for one end of the arm. The contact tip 9 is carried upon the free end of the member 6; this tip being adapted to cooperate with the contact 4. The arm 6 passes through a jaw 10 in the lower end of the plunger and rests upon a and proportions of the contact arm may be selected so as to make it as light as possible and of a resiliency adapted to give the proper wiping engagement between the contact tips and to hold them together through the proper degree of spring pressure. The conductors 14 may be soldered or otherwise fastened to the member 6 between the tip and a point 16 near the point of support, thus mak mg a compact and secure construction.

The parts are so arranged that in closing the contactor the contact 4 and tip '9 first engage at their extreme outer ends, the ti 9 then wiping across the contact 4 and rocking upon it, until finally contact is made at the inner ends or heels of the contacts and the outer ends are out of engagement with each other. In opening, the wi ing and rocking action is reversed, so that t e circuit is interrupted at the outer ends of the contacts. Thus the burning of the contacts and the consequent roughening thereof due to arcing all take place at their outer ends, while the inner portions, at which the circuit is maintained when,

* terial as long as they permit the wiping and rocking movement above described.

It will be seen that on account of the ivotal support of the contactoi: arm- .an its lightness substantially no resistance is offered to the upward movement of the plunger until the contact tips come into engagement with each other. This is advantageous, inasinuch'as the plunger is practically Without load when the pull thereon is weakest and it is permitted to operate more quickly than has heretofore been possible At the same time the actual contact is made by a strong wiping and rocking movement and maintamed with the desired pressure.

What I claim as new and desire to secure by Letters Patent of the United States, is,

1. In an electromagnetic switch, a plunger carrying a strip of spring metal hinged at its one end, a contact on its other end, a cooper-- ating fixed contact, the engaging surface of said first named contact being inclined to the surface of the second named contact, whereby upon the operation of the switch first the outer ends of the contacts engage,

and thereafter a rocking action of the first named contact brings the inner ends of the contacts into'engagement and separates the tips I 2. An electromagnetic switch comprising a fixed contact, and a movable contact operother at their outer ends, and means engaging said strip of spring material for moving the movable contact member about its pivot and bringing the'contact tip into engagement with the fixed contact and rocking it thereon until engagement takes place at the inner ends of said tip and fixed contact.

4. In a power-operated switch, a fixed contact member, a movable contact member composed of a strip of spring material pivotally supported at one end and having a contact tip at its free end, a flexible conductor arranged substantially arallel with said strip and having one en connected to said contact tip and its other end arranged in a loop about the ivot of said strip and secured to a fixe terminal, and an electromagnet having its plunger loosely connected to said strip for operatin the same.

In witness whereof, f have hereunto set my hand this 8th day of February, 1906.

GEORGE H. HILL. Witnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

